The fluorescence method has conventionally been used for sensitive detection of a biochemical. Since this method is easy to utilize compared with a technique using a radioisotope adopted theretofore and no safety measure against radioactivity is needed, the technique was quickly replaced by the fluorescence method. The fluorescence method includes a method of directly labeling a biochemical to be detected with a fluorescent substance, and a method of indirect labeling. If a fluorescent immunological test is taken as an example, in the former method, a biochemical to be detected is directly labeled with a fluorescent substance and then a fluoresceinated biochemical is captured by an antibody immobilized on a solid phase for detection. The so-called competitive method is also included in this category. The latter method includes a sandwich assay in which an antibody having an affinity for the same biochemical is fluoresceinated to allow a secondary reaction.
On the other hand, the chemiluminescent assay has been developed. Since scattered excitation light is not measured as a background light in the case of chemiluminescence, more sensitive measurement can be performed. For chemiluminescence, a biochemical to be detected is directly or indirectly labeled with an enzyme or a fluorescent substance. For the former case, peroxidase or alkaline phosphatase is often used as an enzyme. The so-called enzyme-linked immunosorbent assay falls into this category. An antibody capable of capturing a biochemical to be detected is immobilized on a microplate wall or the like and then a solution containing a substance to be detected is added. The substance to be detected in the solution is captured by the antibody on the wall surface before an excessive solution is washed away. An enzyme labeled antibody for the substance to be detected is added thereto and, after waiting for the enzyme labeled antibody to bind to the substance to be detected, an excessive solution is washed away. Lastly, a solution containing a chemiluminescence reagent that reacts with the enzyme is poured in to detect generated luminescence. If a fluorescent substance is labeled with, for example, as an application of a detector of HPLC, each fluoresceinated molecule flowing out of the HPLC is mixed with a chemical excitation agent for reaction, to detect chemiluminescence emitted by the labeled fluorescent substance being chemically excited.
A technology of arranging beads (hereinafter called a beads array) to which a probe is bonded, in a tube (or capillary tube) is known as a detection device of multiple items (for example, Patent Document 1). Also, a detection device in which a microchannel is used and a molecule capable of capturing a target substance is bonded to a solid phase has been reported (for example, Patent Document 2).    Patent Document 1: Japanese Patent Application Laid-Open No. 11-243997    Patent Document 2: Japanese Patent Application Laid-Open No. 11-075812